1899] 



HESSIAN FLY. 



35 



The accompanying figure shows a young Wheat plant infested by 

 Hessian Fly, the position of the pupa below the ground being shown 



Plant of young Wheat showing,' position of Hessian Fly maggot at a. 

 (After Prof. Webster.) 



at a. In a circular by Prof. Webster, of Lafayette, Indiana, U.S.A 

 from which this figure is copied, giving his experiences of three years- 

 special observation of Hessian Fly maggot attack on young Wheat 

 and from which I quote in my Annual Report for 1887, he mentions 

 that he considered that the winter presence might be detected by 

 peculiarities of the growth and colour of the infested plant. He 

 pointed out regarding the condition of the plant figured, " The plant 

 Itself has not tillered; the leaves are of a darker colour than those of a 

 healthy plant, and proportionally broader. The central spindle-shaped 

 leaf IS missing, and the whole plant is only a bunch of rank-growing, 

 leaves. In any case the darker colour of the leaf, and the absence of 

 the central leaf, together with the bunchy appearance of the part 

 affected, will readily distinguish a fly-infested plant from one not 

 injured."— (F. M. W.) 



This is the state of things where the plant has been attacked before 

 it tillers ; but (as has been remarked) in case the plant has tillered, 

 the Hessian Fly maggot may only attack one, or some of the tillered 

 shoots, and the rest of the tillers may develop into healthy stalks, and 

 give a crop. 



d2 



